title: Leg fat mass as measured by dual X-ray absorptiometry (DXA) impacts insulin resistance differently in obese women versus men.
abstract: OBJECTIVE
  To investigate the association between regional fat mass (FM) and insulin resistance and dyslipidaemia in obese women and men.
  
  
  METHODS
  Body composition was measured by dual-energy X-ray absorptiometry (DXA) in 109 obese women and 113 obese men. Insulin resistance was measured by (HOMA-IR); insulin sensitivity was estimated by metabolic clearance rate (MCRestOGTT) and insulin secretion by HOMAsecr. Serum lipids were assessed.
  
  
  RESULTS
  In women, leg FM was negatively (favourably) associated with HOMA-IR and cholesterol/HDL-cholesterol ratio (p<0.05). Trunk FM was positively (unfavourably) associated with HOMA-IR. Leg/trunk FM ratio was negatively associated with HOMA-IR (p<0.001), cholesterol/HDL-cholesterol ratio (p<0.001) and triglycerides (p<0.01); positively (favourably) with MCRestOGTT (p<0.01) and HDL-cholesterol (p<0.05). No associations were found in men. In women, multiple regression analysis demonstrated that leg/trunk FM ratio was the only explanatory FM for HOMA-IR and MCRestOGTT (R(2) = 0.23 and R(2) = 0.13, respectively; p<0.001), but postmenopausal status was also of importance (R(2) = 0.23, p = 0.019 and R(2) = 0.29, p = 0.015, respectively).
  
  
  CONCLUSIONS
  Leg FM has a favourable influence on insulin resistance and dyslipidaemia in obese women, but not demonstrated in this cohort of obese men.
authors.affiliation: Spesialistsenteret Pilestredet Park, Pilestredet Park, Oslo, Norway. g.aasen@usa.net
authors.forename: Gunnar
authors.initials: G
authors.lastname: Aasen
authors.forename: Hans
authors.initials: H
authors.lastname: Fagertun
authors.forename: Serena
authors.initials: S
authors.lastname: Tonstad
authors.forename: Johan
authors.initials: J
authors.lastname: Halse
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods*; D000273:Adipose Tissue / Q000000981:diagnostic imaging*; D000328:Adult; D000368:Aged; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance; D007866:Leg; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000000981:diagnostic imaging* / Q000503:physiopathology; D017698:Postmenopause; D017697:Premenopause; D012044:Regression Analysis